Method and apparatus for suppressing dust in a mine

ABSTRACT

Air and water are combined in a vessel and propelled under a controlled balanced pressure through a flexible conduit to a remote location where dust is being created. At this location the admixture of air and water is introduced into a double manifold chamber where the air and water separate. The air exerts a preselected pressure on the water through connecting passageways between the two manifolds. The air and water flow through separate passages into one or more nozzles. The nozzles have a turbulence chamber where the air and water are again admixed under the controlled balanced pressure and the admixture is expelled from the nozzles through a plurality of openings as a fine mist. The mist encapsulates the dust particles and removes the dust particles, including the hazardous particles having a size of 10 microns or less, from the atmosphere. In another embodiment the air and water are propelled separately through flexible conduits under controlled balanced pressures to one or more distributors located remotely from the vessel where the water and air are admixed in a turbulence chamber under the same controlled balanced pressure.

169-44. OR 396219918 5R urmcu mares ratent [1113,6213

[72] Inventors Earl M. Damron 3.131446 6/1964 Masuda 239/551 X 1232 Lions Ave., Morgantown, 26500; 2,946, l 85 7/1960 Bayer 239/429 X Harry E. De Witt, 1509 Morgantown Ave., FORElGN PATENTS Fairmont, both of W. Va. 26554 pp NQ 850,074 568 12/1889 Great Britain 169/2 [22] Filed Aug. 14, 1969 Primary Examiner-M. Henson Wood. Jr. [45] Patented Nov. 23, 1971 Assistant Examiner-Edwin D. Grant Allorney-Stanley J. Price, Jr.

[54] METHOD AND APPARATUS FOR SUPPRESSING DUST IN A MINE ABSTRACT: Air and water are combined in a vessel and 7 Claims, 5 Drawing Figs. propelled under a controlled balanced pressure through a flex- [52] 0.8. CI 169/2, lble condun to a remote location where dust IS bemg created.

At this location the admixture of air and water is introduced 239/337239/369 into a double manifold chamber where the air and water 51 rm.c|..... as; separate The air exerts a preselected pressure on the 50] Field of Search 239/2, 8, passageways between mamfdds' The air and water flow through separate passages into one or I 5 more nozzles. The nozzles have a turbulence chamber where l the air and water are again admixed under the controlled 56] References Chad blalarilced prlessulre thte admixture is expelledtfrlorrn the tr g:-

2 es roug a p ura r y o openings as a me mlS e mls UNITED STATES PATENTS capsulates the dust particles and removes the dust particles.

l62,920 5/187 Henry 169/2 including the hazardous particles having a size of 10 microns Steffens... Q1- less from the atmosphere 1,080,594 /1 1 l 'n 2 /429 In another embodiment the air and water are propelled 3 6/1917 l69/2 separately through flexible conduits under controlled 1,376,082 /19 1 Dodds 169/2 balanced pressures to one or more distributors located l 1 10/1923 Blcrsdol'f- 239/352 x remotely from the vessel where the water and air are admixed 1.5 4. 41 2 /192 rr a 239/3 in a turbulence chamber under the same controlled balanced 2,9l9,704 H1960 Butler... 239/8 X pre5 ure Re. 24,771 1/1960 Seibel .1: 239/433x- 6'6 5s\ 64 54 0 I 62 F llllll 78 68 60 PATENTED V 23 I971 SHEET 3 [IF 4 INVENTORS EARL M. DAMflO/V and HARRY E. 00 WIT?" fgjl; 4

flu/r Alla/nay PAIENTEBNUv 23 |9Tl 3.621 .918 sum u or 4 FIG. 5

valor vii l 44 lllll. llllllllllll $3,:

l f? m4 IN VENTORS EARL M. DAMRON 00d HARRY E DOW/77' METHOD AND APPARATUS FOR SUPPRESSING DUST IN A MINE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method and apparatus for suppressing dust in a mine and more particularly to a method and apparatus for supplying air and water at a controlled balanced pressure to one or more spray nozzles for discharge into the atmosphere as a fine mist.

2. Description of the Prior Art Presently used conventional spray devices for reducing dust in the atmosphere require substantial volumes of water at high pressures. For example, with the presently used devices between 30 and 40 gallons of water are discharged as a spray with pressures up to 700 p.s.i. This large volume of water saturates the mined product and either reduces its value or requires further processing to remove the water therefrom. The large volumes of water also cause drainage problems in the mine and increase the maintenance of the haulageways. The large volume spray devices presently used are ineffective to remove the hazardous dust particles having a size of 10 microns or less. There is a need, therefore, for dust suppression apparatus that reduces the volume of water required and more effectively removes the extremely fine dust particles having a size of 10 microns or less.

SUMMARY OF THE INVENTION According to the present invention air and water are transported under a preselected controlled balanced pressure from a vessel to a remote location. At the remote location the air and water are admixed in a turbulence chamber of one or more nozzles and expelled through openings in the nozzles to the atmosphere as a fine mist. The dust particles are encapsulated by the fine mist and are removed from the atmosphere.

The controlled balanced pressure of the air and water reduces BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates the apparatus for subjecting the water to a predetermined pressure in a vessel and for admixing the water with air at the same pressure.

FIG. 2 is a view in front elevation of a distributor manifold with portions broken away illustrating the manner in which the admixture of air and water under balanced pressure is separated in the manifold and thereafter introduced into the nozzles.

FIG. 3 is a view in section taken along the line 3-3 of FIG. 2.

FIG. 4 is a view of apparatus for transporting air and water under a predetermined balanced pressure to remotely located distributor nozzles.

FIG. 5 is a view in section similar to FIG. 3 illustrating another embodiment of the distributor nozzle.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings and particularly FIGS. 1-3, there is illustrated a pressure vessel having a water inlet conduit 12, an air inlet conduit 14 and a water outlet conduit 16. Water is introduced through conduit 12 at a preselected pressure, as for example 125 p.s.i., into the vessel 10. A water level control device 18 associated with electrodes 20 within the vessel 10 and the valve 22 control the water level 30 within the vessel 10. Air under pressure is introduced into conduit 24 from a suitable source and flows through a check valve 26 to a T-connection 28 that connects air conduit 24 with conduit 14 which in turn connects conduit 24 with pressure vessel 10. With this arrangement the water in pressure vessel 10 is subjected to the same pressure as the air flowing through conduit 24. A gate valve 32 is positioned in the air conduit 24 on the downstream side of the T-connection 28 and is open when the system is in operation. The outlet conduit 16 for the water under pressure has a control valve 34 that is also open when the system is in operation. A safety valve 36 is provided for vessel 10 and is preferably set to open at l0 p.s.i. above the normal working pressure which may be about 100 p.s.i.

Spaced from the vessel 10 is a mixing device 38 that has an inlet 40 connected to conduit 16 and the water flowing through conduit 16 is introduced into the mixing device 38 through inlet 40. Similarly, air under pressure flowing through conduit 24 is introduced into the mixing device 38 through inlet 42. The air and water at the same balanced pressure are admixed in the mixing device 38 and the admixture is conveyed through the flexible conduit 44 at this balanced pressure to the manifold generally designated by the numeral 46 and illustrated in FIG. 2. The manifold 46 may be positioned on a mining machine or on other mechanical equipment adjacent themine face where substantial dust is created during the mining operation. The manifold 46 may also be remotely positioned in haulageways, air passages at material transfer points such as locations where mined material is discharged from a shuttle-type vehicle onto a conveyor belt, or where the mined material is transferred from a conveyor belt .to rail-type haulage vehicles. In certain mining installations the mined material is transferred from one endless conveyor belt to another and a manifold may be positioned at that location to suppress the dust created by the mined material being discharged from one endless conveyor belt onto a second endless conveyor belt located therebelow.

Referring to FIG. 2, the manifold 46 has a lower chamber 48 and a parallel spaced upper chamber 50. The chambers 48 and 50 have connecting passageways 52 therebetween. The admixture of water and air enters the lower chamber 48 through conduit 44 and the air separates from the water because of the relative size of chamber 48 and conduit 44. The air flows upwardly through the connecting passageways 52 into the upper chamber 50. With this arrangement the chamber 48 contains water and the chamber 50 contains air both at the same pressure.

The air and water are discharged from the manifold 46 through a plurality of spray nozzles generally designated by the numeral 54 and illustrated in detail in FIG. 3. The nozzles 54 have a body portion 56 with a turbulence chamber 58 and an outlet cover 60 with a plurality of orifices 62 therein. The body portion 56 has a vertical opening 64 communicating with the upper chamber 50. A tube 66 is connected to the opening 64 and extends upwardly into the chamber 50. Air flows downwardly through tube 66 into the opening 64 and into an annular passageway 68. A plurality of lateral passageways 70 connect the annular passageways 68 with the turbulence chamber 58 to thus introduce air through the passageways 70 into the turbulence chamber 58. The nozzle body portion 56 has a chamber 72 with a vertical passageway 74 extending downwardly therefrom that is connected to a tube 76 positioned in the lower chamber 48 below the liquid level therein. A horizontal passageway 78 connects the chamber 72 with the turbulence chamber 50 and permits the water to flow into the turbulence chamber 58 between the airflow passages 70. A valve member 80 is positioned in the chamber 72 and is arranged to extend into the horizontal passageway 78 to thereby throttle the flow of water therethrough. With the above arrangement the air from chamber 50 and water from chamber 48 at the same pressure are remixed in the turbulence chamber 58 and expelled through the nozzle plate orifices 62 as a fine mist or spray.

The orifices 62 in outlet cover 60 are designed both as to number and size so that they do not demand the volume available from turbulence chamber 58 and the mixture of air and water therefore remains at system pressure. The orifices 62 are so shaped to hold the air at system pressure as long as possible in order to provide a greater expansive force adjacent the orifice outlets. This minimizes the air velocity adjacent the orifice outlet as is inherent in present spray systems.

In FIG. 4 there is illustrated another embodiment of the apparatus for remotely transporting air and water under balanced pressure to a distributor device that includes a nozzle. The distributor and nozzle illustrated in FIG. 4 are positioned for illustrative purposes adjacent a conveyor transfer point where mined material is transferred from an upper endless belt generally designated by the numeral 100 to a lower endless conveyor belt generally designated by the numeral 102. An actuator switch 104 which is actuated by a load of mined material on the upper surface of belt 102 controls the air valve 106, water valve 108 and also, through control device 110, opens the valve 112 to permit water to flow into vessel 114 until a water level 116 reaches a preselected height where the water level valve 118 through control device 110 closes valve 112. Similar to FIG. 1, water is supplied through conduit 120 to the vessel 114. The water flows from vessel 114 through conduit 122 that has a stand leg 124 extending downwardly into the body of water within the vessel 114. Air under pressure flows through conduit 126 to a T-connection 128 where it flows downwardly through branch conduit 130 into vessel 114 above the water level 116. The conduit 126 on the opposite side of valve 106 has a T-connection 132 with flexible conduits 134 and 136 connected thereto. For exemplary purposes, conduit 136 is indicated as terminating adjacent the T-connection 132. It should be understood, however, that the conduit 136 may be connected to other distributors in a manner similar to conduit 134.

The conduit 122 on the downstream side of valve 108 has a similar T-connection 138 with flexible hoses 140 and 142 connected thereto. With this arrangement air under system pressure is transported through conduit 134 to a plurality of distributor devices generally designated by the numeral 144 and water is transported through the flexible conduit 140 to the distributors 144 under the same system pressure. Thus the distributors 144 have both air and water continually supplied thereto at a balanced controlled system pressure through the respective conduits 134 and 140. The distributor devices 144 may be positioned at any location to provide the fine water mist, preferably where the dust is created. For example, in FIG. 4 one distributor device 144 is aimed so that a fine mist of water is provided directly above the location where the mined material is transferred by gravity from the upper belt 100 to the lower belt 102. A second distributor device is aimed to provide a fine mist in a direction adjacent the rear face of the material as it is discharged from the upper belt to the lower belt.

The distributor device 144 is illustrated in detail in FIG. and includes a body portion 146 with a water inlet 148 and a water outlet 150. Both the water inlet and water outlet open into a chamber 152. The distributor body portion has an air inlet 154 and an air outlet 156 that communicate with an annular air passageway 158. The distributor 144 includes a turbulence chamber 160 with nozzle outlet cap 162 having a plurality of outlet orifices 164. The nozzle portion of distributor 144 is similar to the nozzle portion of the nozzle 54 and includes a horizontal water passageway 166 that connects the chamber 152 with the turbulence chamber 160 and lateral passageways 168 that connect the annular air passageway 158 with the turbulence chamber 160. An adjusting valve 170 is also provided for throttling the flow of water through the water passageway 166. With this arrangement, water and air are supplied under balanced controlled pressure through inlets 148 and 154 through the connecting passageways to the turbulence chamber 160 where the water and air under this balanced pressure are admixed and expelled through the oriflees-164.

OPERATION With the apparatus illustrated in FIGS. 1 and 2, air is supplied through conduit 24 to the upper portion of vessel 10 through the air inlet conduit 14 and water is supplied through conduit 12 to the vessel 10. The level of the water within the vessel 10 is controlled by the level indicator 20 and valve 22. The flexible conduit 44 is connected to the manifold 46 located remotely from the vessel 10 and preferably adjacent the source of dust. Valves 32 and 34 are open and pressurized water and air flow through respective conduits 16 and 24 to the mixing device 38 where the water and air are admixed and flow through conduit 44 to the manifold 46. In manifold 46 the air and water separate and the air moves upwardly to the chamber 50 while the water 48 under system pressure remains in chamber 48. The air and water are introduced at system pressure into the nozzle 54 where, in the turbulence chamber 58, they are admixed and expelled as a fine spray through the orifices 62.

The embodiment illustrated in FIG. 4 differs from that illustrated in FIG. 1 in that the water and air are transported separately at system pressure through the conduits 134 and to the distributor devices 144 where they are admixed in the turbulence chamber (FIG. 5) and discharged through the orifice outlet 164 as a fine mist or spray.

The above-described apparatus automatically combines under equal pressure a predetermined volume of water with a predetermined volume of air. The admixed air and water at system pressure is discharged through the outlet orifices to form minute particles of water that literally float through the atmosphere to cleanse the air of dust particles of every size.

The water and air transported through the conduit 44 (FIGS. 1 and 2) or the conduits 134 and 140 (FIG. 4) may be used to cool both the electrical and hydraulic equipment on mobile mining apparatus. The air and water conveyed through the flexible conduit or hose 44 can thus be used to perform cooling functions on the mining machine and eliminate the necessity of an additional hose for the cooling purpose. The spray nozzle portion of the apparatus is an essential element of the system and is most efficient when used with the automatically balanced pressure conduits above discussed. The turbulence chamber of the nozzle assembly provides a chamber for violent and necessary agitation of the water and air and also functions as a pressure vessel where the agitated mixture is held at system pressure until released into the atmosphere. The above-described method and apparatus is unique in that it cleanses the air of dust particles substantially every size, and particularly having sizes of 10 microns or under. The air is cleansed with the nozzle portion located remote from the pressure vessel at a point near where the dust is being created. This differs from conventional systems. The method and apparatus above-described permits little, if any, dust to escape into other areas of the mine to create safety hazards.

The result of dust sampling of a crusher room and slope bottom in a mine in which the apparatus above-described was installed, taken at points 20 feet in front of and 20 feet behind the crusher while in operation, illustrated that while another spray system was in operation the density of the dust particles at the sampling point increased. The dust content, however, of the air was reduced by 45 percent during the period in which the above-described apparatus was in operation. Sampling of the l0 micron dust particles present in the air in the crusher area indicated a 32.6 percent reduction, whereas with conventional sprays the percent reduction of -IO micron dust particles was about i: of 1 percent.

According to the provisions of the patent statutes, we have explained the principle, preferred construction and mode of operation of our invention and have illustrated and described what we now consider to represent as its best embodiments.

We claim:

I. A method for suppressing dust in a mine comprising,

introducing air at a preselected pressure into a vessel,

introducing water into said vessel so that said water is subjected to said preselected pressure of said air,

introducing said water under said preselected pressure into a turbulence chamber of a nozzle, introducing air at said preselected pressure into said chamber, admixing said air and said water at said preselected pressure in said chamber, and discharging said admixture from said chamber through openings in said nozzle as a fine mist into the atmosphere to thereby encapsulate the dust particles and remove the dust particles from the atmosphere in a mine. 2. A method for suppressing dust in a mine as set forth in claim 1 which includes,

withdrawing said water from said vessel and transporting said water under said preselected pressure through a conduit to a remote location, thereafter introducing said water into said chamber of said nozzle, transporting said air under said preselected pressure through a conduit to said remote location, and thereafter introducing said air into said chamber of said nozzle. 3. A method for suppressing dust in a mine as set forth in claim 1 which includes,

withdrawing said water from said vessel under said preselected pressure, admixing said water under said preselected pressure with air at said same preselected pressure, and transporting said mixture of air and water at said preselected pressure through a conduit to a remote location. 4. A method for suppressing dust in a mine as set forth in claim 3 which includes,

separating said air and water mixture in a second vessel so that said water is subjected to said preselected pressure from said air under pressure and thereafter introducing said air and water into said nozzle turbulence chamber. 5, Apparatus for suppressing dust in a mine comprising,

a pressure vessel having first inlet means for introducing water into said vessel at a pressure above a preselected pressure and second inlet means for subjecting said water in said vessel to a preselected air pressure,

a noule having an air inlet, a water inlet, a turbulence chamber and outlet openings,

said pressure vessel having outlet means for withdrawing said water from said vessel at said preselected pressure and introducing said water at said preselected pressure through said water inlet into said nozzle turbulence chamber,

means for introducing air at said preselected pressure into said turbulence chamber for mixing therein with said water at said preselected pressure so that said mixture of air and water is discharged from said nozzle as a line mist to encapsulate dust particles in the atmosphere,

a mixing device connected to said vessel outlet means, said mixing device having an air inlet and an outlet,

a manifold positioned remotely of said pressure vessel, and

a conduit connecting said mixing device outlet and said manifold,

said manifold having means to separate said air and water and introduce said air and said water both at said preselected pressure into said nozzle turbulence chamber.

6. Apparatus for suppressing dust in a mine as set forth in claim 5 which includes,

conduit means connecting said pressure vessel outlet means with said nozzle water inlet means to convey water at said preselected pressure to said nozzle turbulence chamber.

7. Apparatus for suppressing dust in a mine as set forth in claim 5 in which,

said manifold includes an upper chamber and a lower chamber with a vertical passageway therebetween, and

said lower chamber connected to said nozzle water inlet and said upper chambe: cogne ted to said nozzle air inlet. 

1. A method for suppressing dust in a mine comprising, introducing air at a preselected pressure into a vessel, introducing water into said vessel so that said water is subjected to said preselected pressure of said air, introducing said water under said preselected pressure into a turbulence chamber of a nozzle, introducing air at said preselected pressure into said chamber, admixing said air and said water at said preselected pressure in said chamber, and discharging said admixture from said chamber through openings in said nozzle as a fine mist into the atmosphere to thereby encapsulate the dust particles and remove the dust particles from the atmosphere in a mine.
 2. A method for suppressing dust in a mine as set forth in claim 1 which includes, withdrawing said water from said vessel and transporting said water under said preselected pressure through a conduit to a remote location, thereafter introducing said water into said chamber of said nozzle, transporting said air under said preselected pressure through a conduit to said remote location, and thereafter introducing said air into said chamber of said nozzle.
 3. A method for suppressing dust in a mine as set forth in claim 1 which includes, withdrawing said water from said vessel under said preselected pressure, admixing said water under said preselected pressure with air at said same preselected pressure, and transporting said mixture of air and water at said preselected pressure through a conduit to a remote location.
 4. A method for suppressing duSt in a mine as set forth in claim 3 which includes, separating said air and water mixture in a second vessel so that said water is subjected to said preselected pressure from said air under pressure and thereafter introducing said air and water into said nozzle turbulence chamber.
 5. Apparatus for suppressing dust in a mine comprising, a pressure vessel having first inlet means for introducing water into said vessel at a pressure above a preselected pressure and second inlet means for subjecting said water in said vessel to a preselected air pressure, a nozzle having an air inlet, a water inlet, a turbulence chamber and outlet openings, said pressure vessel having outlet means for withdrawing said water from said vessel at said preselected pressure and introducing said water at said preselected pressure through said water inlet into said nozzle turbulence chamber, means for introducing air at said preselected pressure into said turbulence chamber for mixing therein with said water at said preselected pressure so that said mixture of air and water is discharged from said nozzle as a fine mist to encapsulate dust particles in the atmosphere, a mixing device connected to said vessel outlet means, said mixing device having an air inlet and an outlet, a manifold positioned remotely of said pressure vessel, and a conduit connecting said mixing device outlet and said manifold, said manifold having means to separate said air and water and introduce said air and said water both at said preselected pressure into said nozzle turbulence chamber.
 6. Apparatus for suppressing dust in a mine as set forth in claim 5 which includes, conduit means connecting said pressure vessel outlet means with said nozzle water inlet means to convey water at said preselected pressure to said nozzle turbulence chamber.
 7. Apparatus for suppressing dust in a mine as set forth in claim 5 in which, said manifold includes an upper chamber and a lower chamber with a vertical passageway therebetween, and said lower chamber connected to said nozzle water inlet and said upper chamber connected to said nozzle air inlet. 